Along with the recent spread of radio communication technologies, an environment is being established in which multiple radio communication systems of different communication schemes can be utilized at the same time. For example, consideration has been made to provide a radio communication device which is connectable to both of a system of cdma2000 n x evolution-data only (EV-DO) which is one of the third generation cellular phone systems, and a wireless MAN system (mobile WiMAX) which is defined by IEEE802.16e or the like.
Such a radio communication device connectable to multiple radio communication systems monitors a condition of a radio signal (for example, RSSI) received from a radio base station in connection, quality of throughput or the like. Thereby, the radio communication device can execute handover to a radio base station in another radio communication system before ongoing communication is cut by deterioration of the quality (for example, Patent Document 1).    Patent Document 1: JP-A 2004-561996 (pages 11 and 12, FIG. 5)